Common Map Turtle
Graptemys geographica
Excerpted from: Animal Diversity
Common Map Turtle
Graptemys geographica
|
Lifespan
|
6 years
|
Length
|
Males: 6.2 inches
Females: 10.5 inches
|
Color
|
The lines on the carapace are a shade of yellow or orange and are
surrounded by dark borders. The rest of the carapace is olive or grayish brown.
|
Gestation Period
|
75 days
|
Clutch Size
|
10 to 12 eggs
|
Diet
|
Snails, clams, crayfish and aquatic insects
|
Common Map Turtles get their name from the markings on the carapace. The light
markings resemble waterways on a map or chart. The lines on the carapace are a
shade of yellow or orange and are surrounded by dark borders. The rest of the
carapace is olive or grayish brown. The markings on the older turtles may be barely
visible because of darker pigment.
The carapace is broad with moderately low keel.
The hind of the carapace is slightly scalloped shaped due to the scutes. The plastron
of an adult map turtle tends to be plain yellowish color. The head, neck and limbs
are dark olive, brown or black with thin yellow, green or orangish stripes. There is
also an oval spot located behind the eye of most specimens.
There is sexual dimorphism in size and shape. The females are much larger than the
males. The males also have a more oval carapace with more distinct keel, narrower
head, longer front claws, and a longer thicker tail. The males vent also opens beyond
the edge of the carapace whereas the female's open up the carapace. The young Map
Turtles have a pronounced dorsal keel and patterns on the plastron consist of dark
lines bordering the scutes. A hatchling has rounded gray or
grayish-brown carapace about 1 inch long. The pattern is light circular markings. The
stripes located on the head and limbs are just like the adults.
In the wild Common Map Turtles are estimated to live up to 6 years.
The Common Map Turtle is dormant from November through early April. Most of that
time is spent under the water, wedged beneath submerged logs, in the bottom mud of
a lake or in a burrow. They have been known to change locations in the middle of the
winter. They are avid baskers and they bask in groups. They are diurnal, active both
in the day and at night (Harding 1997). They are also a very wary animal, at the slightest
hint of danger they slip into the water and hide.
During courtship the male initiates by tapping his long claws on the front of the female
but few details are known.
Common Map Turtles are omnivores. The feeding always takes place in the water. The
adult females, due to their large heads and strong jaws eat larger prey than the males.
The females consume snails, clams, and crayfish. The males eat aquatic insects, snails,
and smaller crustaceans. Both are also known to eat dead fish and some plant material.
Beavers — Nature's Hydrologist, Part 2
Garter Snakes — The Gardener's Friend
Wisconsin Native Salamanders
Goundhog or Woochuck: All The Facts
Voles, Both The Good and The Bad